This deck requires heavy investment and Box resets, but having multiple Relinquished, along with the supports to summon him faster can be really strong. This is mostly an "all-in" version of the deck, without using cards like Interdimensional Matter Transporter to protect it, and focusing on its ability to get summon multiple Relinqsuihed.
There are 2 ways to use Relinquished, take control of your opponent's strong monster to beat their weaker ones, or take their weaker ones and attack into their stronger ones to deal damage. The latter only works if your opponent's LP is lower than yours, and if the damage that you take does not finish you off right away, while the former is good if you want to play offensively.
A common strategy that people sometimes do early in the duel, when your opponent only has 1 set monster and you can summon Relinquished, summon a monster, then summon Relinquished and take their set monster. This can potentially allow you to direct attack your opponent early. Having them at lower LP than you will give you quite a huge advantage in a Relinquished deck. You also don't have to be very conservative about using Sphere Kuriboh to defend, since you can use Sphere as the sacrifice material to get Relinquished out.
With only 3 Harpies in the deck, and no way to search for them, they won't be appearing as often, but the threat of Harpies' Hunting Ground field spell can make your opponent play more cautiously about their spell/trap cards.
Sonic Bird and Senju of the Thousand Hands will be summoned in preference to Harpies. Summoning Harpies to destroy a face-up spell/trap card like Mirror Wall and Skull Lair is the best. That's safer than destroying face-down spell trap cards since people often bring HHG counter cards like Security Orb, or Wild Tornado.
Additionally, in a Relinquished deck, Harpies can be used to destroy your Relinquished's equipped card instead of your opponent's spell/trap. Then your Relinquished can take a monster your opponent controls again.
Interdimensional Matter Transporter
|Banishing your Relinquished will make them untargetable and destroys the equipped monster.|
|Available card boxes|